Refrigerating apparatus



Feb. 10, 1931. G. ANDRESEN- REFRIGERATING APPARATUS Filed April 25, 1927 Patented Feb. 10," 1931 UNITED STATES PATENT OFFICE GEORGE ANDRESEN, OF CHICAGO, ILLINOIS, .ASSIGNOR TO W. B. PARKYN, OF CHICAGO,

ILLINOIS REFRIGERATING APPARATUS Application filed April 25,

My invention relates more particularly to refrigerating apparatus of the so-called flooded type in which the evaporator element, as for example a coil, is filled at all timeswith the liquefied refrigerating agent supplied thereto under the control of any suitable means, as for example a float-controlled valve,

located in a receptacle incommuni'cation with the coil and into which the liquid-refrigerantsupply pipe opens.

such systems where the. gas in liquefied condition is heavier than the lubricating oil supplied to the compressor, the oil accumulates in the float chamber referred to forming a layer on the upper surface of the body of liquefied refrigerant therein, and presenting great objections in structures as hitherto provided, as is well understood in the art, due'to the fact that the refrigerant which becomes gasified in performing the refrigerating function, is required to pass upwardly, in gaseous form, through the layer of oil referred to, in its travel back to the compressor for recompression and liquefaction and subsequent discharge to the evaporator coils, the oil layer referred to blanketing the free flow of the gas to the inlet of the com pressor and interfering with the desired maximum functioning of the machine.

My object is to provide a construction by which the passage of the gasified refrigerant through the oil layer referred to, in its travel to the inlet of the compressor, will be obviated and thereby overcome the objections incident to the requirement that the gasified refrigerant pass through such layer. 7

Referring to the accompanying drawings Figure 1 is a view in vertical sectional elevation of an evaporator element of the socalled flooded type in which my invention is incorporated. Figure 2 is a section taken at the line 2 on Fig. 1 and viewed in the direction of the arrow; and Figure 3, a view some-what diagrammatic, of a refrigerating system in which my improved evaporator element is incorporated.

As a preface to the following description of the illustrated construction, it may be stated that my invention consists primarily in pro- 1927. Serial No. 186,311.

frigerant is conducted to the point .of discharge, thereby avoiding the necessity of drawing the gas through the'layer.

In the accompanying drawings I have shown my invention as applied to a refrigeratmg system employing an evaporator element of the flooded-type and of common construction and comprising a receptacle 3 openmg into the upper ends ofa series of U'-pipes 4 which would be located in a refrigerating brine-tank, or extend into a space to be refrigerated. The receptacle 3' forms a floatchamber into which opens a pipe 5 which in practice would lead from any suitable source of liquefied refrigerant which in liquefied condition is heavier than the lubricating oil used in the compressor, as for example from a condenser, such as that shown at 100, to which the compressedgasified refrigerant is supplied from a compressor, as for example that shown at 101, the inlet of which is in, communication with the upper portion of the receptacle 3. The receptacle 3 is provided with a valve 6 for controlling the flow of the liquefied refrigerant from the pipe 5 into the receptacle 3, this valve being controllable, by a float-device 7 for maintaining in the receptacle 3 and pipes 4 the desired depth of body of liquefied refrigerant. The outlet from the receptacle 3 for the refrigerant which becomes gasified in the pipes 4 in performing the refrigerating function, and through which the gasifiedrefrigerant is conducted to. the compressor 101 for compressing the gasified refrigerant, is represented at 8, this pipe opening into the upper portion of the receptacle 3 above the level of the liquefied gas therein.

In accordance with the particular illustrated embodiment of my invention, I provide in the receptacle 3 a pair of vertically extendingpipes 9, each shown as a segment of an annulus and open at opposite ends and horizontal plane of the oil layer referred to and represented diagrammatically at 10, and the upper ends of these pipes opening above said layer and preferably above the inlet of the pipe 8, the pipes 9 being of such length that they will occupy the respective positions stated relative to the oil layer 10, regardless of variations in the height at which such layer extends.

In the operation of the apparatus the refrigerant, which becomes gasified in the pipes 4 in the refrigerating operation, rises through the open ends of these pipes into the liquid refrigerant in the receptacle 3 and enters the lower ends of the pipes 9 through which it passes-upwardly and discharges at the open ends thereof into the receptacle 3 above the oil layer 10 therein and thence passes, to-

gether with such of the oil as overflows into the pipe 8 when the oil level reaches this point, into the pipe 8 and into the inlet of the compressor, under the suction action of the latter, the gas thus passing around, instead of through, the oil layer 10, with the manifest advantage.

The by-pass arrangement shown provides sufiicient passage of the gas from the bath into the space above the bath as to approximately equalize the pressure above and below the oil blanket therebycausing the device to function to overcome the disadvantages resulting from the blanketing of the oil.

In the discharge of the oil and liquefied refrigerant into the chamber 3 such separation takes place that all except possibly a very small proportion of the oil rises and forms the blanket, this small proportion only passing into the pipes 4. Defined in another way, only such oil as is taken up by the refrigerant due to the mutual solubility of these liquids, passes into the pipes 4. While it is possible that some oil willbe found on the top of the liquefied refrigerant in the pipes 9, a relatively thin film onlyrof this oil would exist as compared with the relatively heavy blanket of oil on the bath in the chamber 3, but such oil is quickly discharged through the outlets of the pipes 9 under the boiling action of the refrigerant in performing the refrigerating function and the pipes are thus rendered self cleaning of oil. Thus there is no possibility of the building up on the top of the refrigerant in the pipes 9, of a blanket such as is built up in the chamber 3.

While I have illustrated and described a particular construction embodying my invention, I do not wish to be understood as intending to limit it thereto, as the same may be variously modified and altered without departing from the spirit of the invention, and as a suggestion of one of the various modifications which may be made in the structure shown, itmay be stated that, if desired, one of the pipes 9 may be dmitted.

What I claim as new, and desire to secure by Letters Patent, is:

1. In refrigerating apparatus employing a refrigerating medium WhlCh in liquid state is heavier than the oil which becomes mixed therewith in the operation of the compressor, means for compressing a refrigerant in gas: eous condition and liquefying the compressed refrigerant, an evaporator element, means for supplying the refrigerant in liquefied condition from said first-named means to said element and maintaining a body thereof in said element, and means in communication with the body of liquefied refrigerant below the layer of oil thereon for conducting away from said body and into said element above the layer of oil the refrigerant gasified in said body, said element having an outlet between the body of liquefied refrigerant and the point at which said third named means opens into said element above the oil.

2. In refrigerating apparatus employing a refrigerating medium which in liquid state is heavier than the oil which becomes mixed therewith in the operation of the compressor, means for compressing a refrigerant in gaseous condition and liquefying the compressed refrigerant, an evaporator element, means for supplying the refrigerant in liquefied condition from said first-named means to said element and maintaining a body thereof in said element, and means in communication with the body of liquefied refrigerant below the layer'of oil thereon for conducting away from said body into the upper portion of said element the gas evaporated from said body, said element containing an outlet in communication with said first-named means and located between the body of liquefied gas and the point at which said third-named means opens into said element above said body.

3. In refrigerating apparatus employing a refrigerating medium which in liquld state is heavier than the oil which becomes mixed therewith in the operation of the'compressor, means for compressing a refrigerant in "gaseous condition and liquefying the compressed refrigerant, an evaporator element, means for supplying the refrigerant in liquefied condition from said first-named means to said element and maintaining a body thereof insaid element, and a conduit in communication with the body of liquefied refrigerant below the layer of oil thereon for conducting awayfrom said body and into said element above the layer of oil the refrigerant gasified' 'opens into said element above the oil.

4.- In a gas-liquefying apparatus, the combination of a receptacle, an evaporator coil in communication therewith,-means for main-.

taining in said receptacle and coil a supply of liquefied as on'which flats a layer of oil, and means or conducting away from'said receptacle gas generated in said body of liquefied gas comprising a conduit opening at one end only into the body of liquefied gas below the oil layer thereon and at its opposite end above the level .of the liquefied gas and lubricant and through which conduit the gas passes, said element having an outlet disposed above the top of the body of liquefied gas. 7

5. In a gas-liquefying apparatus, thecombination of a receptacle, an evaporator coil located below said receptacle and in communication therewith, means for maintaining in said receptacle and coil a supply of liquefied gas on which floats a layer of oil, and means for conducting away from said receptacle gas generated in said body of'liquefied gas comprising a pipe opening at its upper end into said receptacle above said layer and at its lower end into the body of liquefied gas below the oil layer thereon, and a conduit leading away from the receptacle above the liquid therein.

6. In a refrigerating apparatus employing a refrigerating medium which in liquid state is heavier than the oil which becomes mixed therewith in the operation of the compressor for compressing the gasified refrigerating medium, means for compressing the refrigerant in gasified condition and liquefying the compressed refrigerant, a receptacle, an evap-- orator coil located below said receptacle and in communication therewith, means for supplying the refrigerating medium in liquefied condition from said first-named means to said receptacle and maintaining a body thereof in said receptacle and coil, and means for returning to said compressor the refrigerant gasified in said coil comprising a conduit opening at one end only into the, body of liquefied refrigerant below the layer of oil thereon 'through which the gas passes in its passage to the compressor, said element having an outlet disposed above the top of the body of liquefied refrigerant.

7. In a refrigerating apparatus employing a refrigerating medium which in liquefied state is heavier than the oil which becomes mixed therewith in the operation of the compressor for compressing the gasified refrigerating medium, means for compressing the refrigerant in gasified condition and liquefying the compressed refrigerant, a receptacle, an evaporator coil located below said receptacle and in communication therewith, means for supplying the refrigerant .in liquefied condition from said first-named means to said receptacle and maintaining a body thereof in said receptacle and coil, and means for returning'to said compressor the refrigerant gasified in said coil comprising a conduit opening at one end into the bod of liquefied refrigerant below the layer 0 oil thereon .and at its upper end into said receptacle above said la er, and a conduit opening into said receptac e above said layer and through which the gasified refrigerant passes to said compressor.

8. In a gas-liquefying apparatus, the combination of an evaporator element to which liquefied gas heavier than oil and mixed therewith is supplied, means for defining the level of the liquid in said element, and means providing a gas-passage extending from below the top of the body of liquefied gas to a point above the top of the body of oil thereon for conducting away from the body of liquefied gas in said element the gas evaporated therefrom.

9. In a gas-liquefying apparatus, the combination of an evaporator element to which liquefied gas heavier than oil and mixed therewith is supplied, means for defining the level of the liquid in said element and means pro viding a gas-passage extending from below the top of the body of liquefied gas to a point in said element above the top of the body of oil on said body of liquefied gas for conducting away from the body of liquefied gas in said element the gas evaporated therefrom, said element containing an outletlocated between the body of liquefied gas and the point at which said gas-passage opens into said element above said body.

10. In a gas-liquefying apparatus, the combination of an evaporator element to which liquefied gas heavier than oil and mixed therewith is supplied, means for dfefining the height to which li uefied gas extends in said element, means do ning the height to which oil superposed on the body of liquefied gas extends and forming an outlet for said oil, and means providing a gas-passage extending from below the topof the body of oil thereon, for conducting away from the body of liquefied gas in said element the gas evaporated therefrom. a

11. In a gas-liquefying apparatus, the combination 0 an evaporator element to which Qliquefied gas heavier than oil and mixed therewith is supplied, means defining the level of the liquid in said element, and a by-pass for conducting the gasified refrigerant from the the gas-flow is'not subject to impedance by the layer of oil.

14. The method of evaporating liquid refrigerant, covered by a layer of oil, in the production of refrlgerating. temperatures which consists in by-passing the gas evaporated from the body of refrigerant around the layer of oil to avoid overcoming, by the gas-flow, of impedance by the layer of oil.

15. The method of evaporating liquid refrigerant, covered by a layer of oil, in the production of refrigerating temperatures which consists'in conducting the gas evaporated fromthe body-of refrigerant away from the body thereof to apoilit above the layer of 'oil without the necessity of overcoming the surface tension of the oil.

GEORGE ANDRESEN. 

